JP3129133B2 - Color printing equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color printing apparatus for performing color printing in four colors of cyan, magenta, yellow and black.

[0002]

2. Description of the Related Art Conventionally, a color printing apparatus typified by an ink jet printer or the like for performing color printing using four color inks of cyan, magenta, yellow and black has a print head for each of the four colors. When printing print data sent from an external device such as a host computer, the print data is developed into image data corresponding to print pixels on a one-to-one basis, and the image data is printed in four colors. The print is sent to the head. As described above, since image data is required for the number of heads of the printing apparatus, a memory called a page memory for storing the image data of the four colors is provided. Further, a lot of complicated calculations are required to develop print data into image data, and a memory called a work memory for storing data to be calculated and calculation results is also provided.

[0003]

However, a printing apparatus that performs color printing using such four color inks requires a large-capacity memory. For example, 300dp
A4 by a printing device with a resolution of i (pixels / inch)
To print on paper of the size, the image data per color is 1 Mbyte even if one pixel is 1 bit. Therefore, to store the image data of 4 colors, 4 Mbytes are required only in the page memory. Becomes
In order to develop complex print data using many colors, a large-capacity work memory is required. The provision of these large-capacity memories has been a major factor in increasing the cost of the printing apparatus. In order to reduce the cost of the printing apparatus, it is conceivable to reduce the amount of memory. However, since a certain amount of page memory is required, the amount of work memory is reduced. However, in such a case, it is impossible to develop print data that requires a large-capacity work memory to develop the image data, and such print data cannot be printed. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problem. When the memory capacity of the work data storage unit is insufficient due to the development of complicated print data or the like, a memory area of a part of the page memory is used as a work memory. Therefore, it is an object of the present invention to provide a color printing apparatus which is inexpensive and capable of developing complicated print data without increasing the total amount of memory required in the printing apparatus.

[0004]

In order to achieve this object, a color printing apparatus according to the first aspect of the present invention develops print data including character codes and the like into image image data, and generates cyan image data based on the image image data. A color printing apparatus for performing color printing in four colors of magenta, yellow, and black, wherein the data developing means develops print data into image data, and the data developing means is necessary for developing print data. Work data storage means for storing data, image data storage means for storing each image data of cyan, magenta, yellow, and black developed by the data development means,
A memory shortage determination unit that determines the shortage of the work data storage unit; and, when the memory shortage determination unit determines that the memory is insufficient, the black image image data stored in the image data storage unit is converted into cyan, magenta, and yellow. An image data synthesizing unit for synthesizing each image with the image data and storing the image data in the image data storing unit, and a memory changing unit for changing the black image data storing unit to the work data storing unit. According to a second aspect of the present invention, there is provided the color printing apparatus according to the first aspect, wherein each of the cyan, magenta, and yellow image data combined with the black image image data stored in the image data storage means. And image data separating means for separating the black image data from the image data. According to a third aspect of the present invention, in the color printing apparatus according to the second aspect, a high-speed printing apparatus determines whether or not high-speed printing is designated.
Printing designation determining means, and color printing controlling means,
Color printing control means, wherein a when the memory changing means changes the image data storage means of black working data storage means, high-speed printing designation determining means fast printing finger
When it is determined that the image data has been set, the cyan, magenta, and yellow image data obtained by combining the black image data are read out and printed in three colors . Image de
Data storage means was changed to work data storage means.
The high-speed printing designation determining means has not specified high-speed printing.
If it is determined that the image data is black, the image data separating unit separates the black image data and performs printing in four colors.

[0005]

In the color printing apparatus according to the first aspect of the present invention, the data developing means stores work data necessary for developing print data including character codes and the like into image image data in the work data storage means. While storing the image data, the image data is developed into image data having information corresponding to the print pixels on a one-to-one basis, and the developed image data is stored in cyan, magenta, yellow, and black image data storage units. At this time, the memory shortage determination unit determines whether the work data storage unit is insufficient due to development of complicated print data or the like. If it is determined that the memory is insufficient, the image data combining unit determines whether the work data storage unit is insufficient. Is combined with the cyan, magenta, and yellow image data stored in the image data storage means and stored in the image data storage means. And
The storage area for the black image data of the image data storage means is changed to the work data storage means by the memory change means. Thereby, the capacity of the work data storage means can be increased. Further, in the color printing apparatus according to the second aspect, the image data separating unit stores the cyan, magenta,
And black image image data stored in the image data storage means from yellow image image data. Thus, color printing in four colors can be performed. In the color printing apparatus according to the third aspect, when the black image data storage unit is changed to the work data storage unit, the high-speed print designation determination unit specifies that high-speed printing is specified.
When it is determined that the high-speed printing has been performed, the cyan, magenta, and yellow image data obtained by combining the black image data are read out and printed in three colors. Not specified
If it is determined that the image data does not match, black image data is separated by the image data separating means and printing is performed in four colors. This makes it possible to cope with a case where high quality is required and a case where high-speed printing is required.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a color printing apparatus according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram of a color printing apparatus according to the present embodiment. The color printing apparatus 1 includes a CPU 2 that controls the entire apparatus, an interface 3 that receives print data including character codes and the like from an external apparatus such as a host computer, a print engine 4 that prints on paper, and a printer that generates during operation of the apparatus. The RAM 5 is a volatile memory for storing data that needs to be temporarily stored, and the ROM 6 is a non-volatile memory in which various programs are stored. The CPU 2 is connected to each of the above units, reads out a program from the ROM 6, and performs a predetermined operation.

The RAM 5 is created by a work memory 51 serving as working data storage means for storing data that needs to be temporarily stored when a data expansion program 61 described later operates, and a data expansion program 61. Cyan page memory 5 serving as image data storage means for storing one page of image data for each color of cyan, magenta, yellow, and black
2, a magenta page memory 53, a yellow page memory 54, and a black page memory 55 are provided.

The ROM 6 has a data development program 61 as print data development means for developing the print data received by the interface 3 into image data.
A work memory shortage judging program 62 which is a memory shortage judging means for checking whether the work memory 51 necessary for the operation of the data expanding program 61 is not insufficient, and image data stored in the black page memory 55 A page data synthesizing means 63 for synthesizing the image data stored in the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54, respectively, and a black page memory 55 as a work memory. A work memory change program 64 which is a memory change means for changing to a memory 51;
A page data separation program 65 is provided as image data separation means for separating black image data from image data stored in the magenta page memory 53 and the yellow page memory 54, respectively.

Next, the image data will be described with reference to FIG. FIG. 2A illustrates an example of print data 201 (text data) including a character code and the like.
(B) is a diagram illustrating a graphic 202 in which the print data 201 is allocated on coordinates, (c) is a diagram illustrating bitmap data 203 stored in a page memory, (d) is a diagram illustrating a print output 204, ( 3E is a diagram showing data 205 stored in the work memory 51. The image data is the bitmap data 203 for the print output 204.
Is bit map data having bits corresponding one-to-one with the print pixels, and each page memory is
It has a capacity to store image data corresponding to the number of sheets. The print data 201 of the present example is
The two values before “on” specify the drawing position of the graphic, the “rect” specifies the rectangular shape, and the two values before “rect” sequentially indicate the width and height of the rectangle. The drawing of a rectangle having a width of 5 pixels and a height of 3 pixels at the position of (2, 2) is instructed.

Next, the operation of the color printing apparatus 1 configured as described above will be described focusing on the operation of the data development program 61. As shown in FIG.
Reference numeral 01 denotes text data including elements of position, shape, and color. For example, a rectangle having a width of 5 pixels and a height of 3 pixels is drawn in blue at the position of coordinates (2, 2) as shown in FIG. I have indicated that. When such print data is sent from an external device such as a host computer through the interface 3, the CPU 2 executes a print data development program 61, a work memory shortage determination program 62, a page data synthesis program 63, and a work memory Activate the change program 64 to perform a process of developing print data into image data.

FIG. 3 is a flowchart of a process of developing the image data. When the CPU 2 receives data from the interface 3 (step S1), it checks whether or not the received data is a command to start printing (S2). If the received data is not a print start command but print data (S2 · NO), the print data is sent to the data development program 61, and the work memory 51 is used at the time of print data development based on the position and shape elements of the print data.
Is calculated (S3), and the calculation result is sent to the work memory shortage determination program 62.

The work memory shortage determination program 62
The available memory amount of the work memory 51 is compared with the transmitted work data amount (S4). If the work data amount is smaller than the usable memory amount of the work memory 51 (S4
(YES), the process is returned to the data development program 61, and the print data development process is performed (S5). If the work data amount exceeds the available memory amount (S4: NO), the work memory change program 64 checks whether the black page memory 55 is used as the work memory 51 (S7). If the black page memory 55 has already been used as the work memory 51 (S7
YES), since the work memory 51 cannot be increased, an error message of insufficient work memory is generated, and the process ends (S11). Black page memory 5 still
5 is not used as the work memory 51 (S7
(NO), the available memory amount of the work memory 51 and the memory amount of the black page memory 55 are totaled and compared with the work data amount (S8). If the total amount of memory does not reach the work data amount (S8: NO), an error message of insufficient work memory is generated and the process is terminated (S1).
1).

If the sum of the available memory capacity of the work memory 51 and the memory capacity of the black page memory 55 exceeds the work memory capacity (S8: YES), the image data is synthesized by the page data synthesis program 63 (S9). ). The page data synthesizing program 63 reads the image data of the black page memory 55, performs a logical sum (OR) with the image data read from the cyan page memory 52, and returns the result to the cyan page memory 52. The same operation is performed on the image data stored in the magenta page memory 53 and the yellow page memory 54, and black image data is combined with cyan, magenta, and yellow image data. Next, the contents of the black page memory 55 are cleared by the work memory change program 64 and incorporated into the work memory 51 (S10).
Thereafter, the black page memory 55 is made usable as a part of the work memory 51, the process is returned to the data development program 61, and the print data development process is continued (S5).

FIG. 4 is a flowchart of the print data developing process (S5). Hereinafter, the processing will be described. The drawing start point and drawing end point in the vertical direction are calculated from the position and shape elements of the print data (S101), and are stored in the work memory 51. Next, the process is repeated from the start point to the end point in the vertical direction (S102), and the drawing start point and drawing end point in the horizontal direction at each position are calculated (S103). The calculation results are sequentially stored as raster data in the work memory. 51 is stored.

Next, a page memory to which the bit-mapped data is to be written is selected from the color elements of the print data. First, the black page memory 55 stores the work memory 5
It is checked whether or not the print data is used as one (S104). If it is not used (S104, NO), the color of the print data is separated into four components of cyan, magenta, yellow, and black (S105). ), The write destination of the developed image data is set to the cyan page memory 52,
Magenta page memory 53, yellow page memory 5
4 and the black page memory 55.
When the black page memory 55 is used as the work memory 51 (S104: YES), the color of the print data is separated into three components of cyan, magenta, and yellow (S106), and the developed image is developed. The write destination of the image data is selected from the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54. Regardless of the color separation of four colors and the color separation of three colors, a plurality of page memories may be selected simultaneously depending on the color.

Further, the raster data in the work memory 51 is read out, and is repeated from the start point to the end point in the vertical direction (S107), and is selected in step S105 or step S106 corresponding to the drawing start point and the drawing end point in the horizontal direction. The bit of "1" is set at the position on the selected page memory, and the bit of "0" is set at the page memory not selected (S108). Through the above processing, image data is generated on each page memory.

Next, a specific operation of the print data expanding process (S5) will be described by taking the case of the print data 201 (FIG. 2) as an example. The contents of the print data 201 are as described above. When the print data 201 is input, “2”, which is the drawing position as the start point, is added to the drawing position as the end point, and 1 is subtracted as the end point in step S101. "4" is stored in the work memory 51 as a vertical drawing range. Next, by a loop of steps S102 and S103, step S103 is executed for each of the three points from the ordinate "2" to "4" which are the drawing range in the vertical direction. The drawing range is calculated. In this example, since the drawing is a quadrangle, the drawing range in the horizontal direction is “2”, which is the drawing position as the start point for all points, and “6”, which is obtained by adding the width to the drawing position and subtracting 1 as the end point. Is stored in the work memory 51 as a horizontal drawing range. As a result, the numbers of the start point and the end point are successively stored in the work memory 51, and the data 205 shown in FIG. Data composed of the start point and the end point in this way is called raster data.

If the black page memory 55 has not been changed to the work memory 51 (S104, NO), color separation of four colors is performed in step S105, and the destination of the image data is selected. The print data 201 is b
blue is designated by lue, and when blue is separated into four colors, it becomes cyan and magenta. Even if the three colors are separated in step S106, the same result is obtained in this case. Then, a cyan page memory 52 and a magenta page memory 53 are selected as write destinations of the image data. Then, the raster data of the work memory 51 is read by the loop of steps S107 and S108,
Step S108 is executed for each of three points from the ordinate “2” to “4”, which is the vertical drawing range,
In the memories of the cyan page memory 52 and the magenta page memory 53, “1” is assigned to bits corresponding to the start point “2” of the raster data to the end point “6”,
“0” is set in the yellow page memory 54 and the black page memory. Thus, image image data such as bitmap data 203 (FIG. 2C) is generated in the cyan page memory 52 and the magenta page memory 53. When the image data is generated as described above and the print data expanding process (S5) ends, the data expanding program 61 ends, and the CPU 2 receives the next data from the interface 3 (S1 in FIG. 3).

Returning to FIG. 3, if the received data is a print start command (S2 · YES),
The CPU 2 sends the image data stored in the page memory to the print engine 4 and shifts to print processing.
Upon receiving the print start command, first, it is checked whether the black page memory 55 has been changed to the work memory 51 (S12). When the black page memory 55 is not used as the work memory 51 (S12 · N
O), cyan page memory 52 for cyan, magenta page memory 53 for magenta, yellow page memory 54 for yellow, black page memory 5 for black
As shown in 5, the image data stored in the page memory corresponding to each ink is sent to the print head of the print engine 4, and high-quality printing using four colors of ink is performed (S6).

When the black page memory 55 is used as the work memory 51 (S12 · YE
S), it is checked whether high-speed printing is specified by the print command (S13). If high-speed printing is specified (S13),
13. YES), image data is read from the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54, and the read data is printed by the print engine 4.
(S15) and prints with only the three color inks of cyan, magenta, and yellow (S15). In this case, black is a mixed color of three inks of cyan, magenta, and yellow, and thus becomes slightly brownish due to the color characteristics of the ink. However, image data is read directly from the page memory and printed. Therefore, high-speed printing can be performed as compared with a case where printing is performed by separating page data described later.

When high speed printing is not specified (S13)
NO), the CPU 2 sets the page data separation program 65
Is started to separate black image data from the image data in the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54 (S14). The page data separation program 65 reads image image data from the cyan page memory 52, the magenta page memory 53, and the yellow page memory 54 and performs a logical product (AND). The result is used as black image image data. , And yellow image image data, a logical product (AND) of the image image data read from the page memory and the negation (NOT) of the black image image data is taken, and the logical product (AND) is obtained. I do. Then, the image data of the separated four colors is sent to the print head of the print engine 4, and
High quality printing using color inks is performed (S6). In this case, a portion where three colors of cyan, magenta, and yellow overlap is replaced with black,
Compared to the case of the three colors described above, although it takes some time to separate the black image data, black can be printed with good quality without brown.

As described above, according to the present embodiment, when the image data is expanded in the page memory, the work memory 51 is used.
When the memory capacity of the black page memory 5 becomes insufficient, the black data is superimposed on the cyan, magenta, and yellow page memories 52, 53, and 54.
5 is released and this is changed to the work memory 51.
For example, 1M for print data for A4 size paper
The byte can be used as the work memory 51. When high-speed printing is performed in the case where the memory is changed in this way, a point where data is present in each of the cyan, magenta, and yellow colors is printed as black. Note that the present invention is not limited to the above-described embodiment, and various applications are possible. For example, in the present embodiment, the printing mode is switched by checking whether or not there is a command for performing high-speed printing. However, whether or not this switching process is adopted is optional. The print engine 4 performs printing by an ink jet method, a toner jet method,
A thermal transfer system, a thermal sublimation system, or the like can be employed.

[0023]

As is apparent from the above description, according to the color printing apparatus of the first aspect of the present invention, if there is room in the work data storage means to expand print data, cyan, magenta, It has image data storage means for each color of yellow and black, writes image image data into it, sends it to each print head of 4 colors and prints it, so high-speed printing with high quality color is possible. If there is a shortage of work data storage means for developing print data, the black image data is combined with the cyan, magenta, and yellow image data to store the black image data. Change the means to work data storage means, cyan,
Only the image data storage means for three colors of magenta and yellow are used, and the image data of cyan, magenta and yellow are sent to the print heads of three colors to perform printing. Data can be printed, and the cost can be reduced by reducing the amount of memory of the work data storage means. According to the color printing apparatus of the second aspect of the present invention, when the black image data storage is changed to the work data storage, the cyan, magenta, and yellow image data are converted to the black image data. By separating the data and sending each image data to each print head of four colors, it is possible to print in high quality colors. According to the color printing apparatus of the third aspect of the present invention, when the black image data storage unit is changed to the work data storage unit, the high-speed print designation determination unit specifies high-speed printing.
If it is determined that the high-speed print designation determining unit has read out the image data of each of the cyan, magenta, and yellow images combined with black and prints the image data in three colors,
If it is determined that printing is not specified , black image data is separated and printed in four colors, so that it is used depending on whether high-speed printing is required or high-quality printing is required. Thus, a desired print result can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram of a color printing apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating an example of print data received by a color printing apparatus according to an embodiment of the present invention.

FIG. 3 is a flowchart of an operation of the color printing apparatus according to one embodiment of the present invention.

FIG. 4 is a flowchart of a print data expanding process according to an embodiment of the present invention.

[Explanation of symbols]

 2 CPU 51 Work memory 52 Cyan page memory 53 Magenta page memory 54 Yellow page memory 55 Black page memory 61 Data development program 62 Work memory shortage determination program 63 Page data synthesis program 64 Work memory change program 65 Page data separation program

Claims (3)

(57) [Claims] 1. Print data consisting of a character code or the like is developed into image image data, and based on the image image data .
4 for cyan, magenta, yellow, and black
In a color printing apparatus that performs color printing with colors, data development means for developing the print data into image image data, and work data for the data development means to store data necessary for the work of developing the print data Storage means, cyan, magenta developed by the data developing means,
Image data storage means for storing each image data of yellow and black; memory shortage determination means for determining shortage of the work data storage means; and when the memory shortage determination means determines that there is insufficient memory, Image data synthesizing means for synthesizing the black image image data stored in the image data storage means with each of the cyan, magenta, and yellow image image data and storing the image data in the image data storage means; A color changing device for changing the data storage means to the work data storage means. 2. An image data separating means for separating black image data from each of cyan, magenta and yellow image data, which are stored in the image data storing means and are combined with the black image image data. The color printing apparatus according to claim 1, further comprising: And determining whether high-speed printing is designated.
A high-speed printing designation determining unit and a color printing controlling unit.
Further, the color print control means is provided when the memory change means changes the black image data storage means to work data storage means, and the high-speed print designation determination means
If it is determined that the printing is designated, cyan black picture image data is synthesized, magenta, and performs printing in three colors by reading each image image data of yellow, the memory changing means Black
Change the image data storage means to work data storage means
The high-speed printing designation determination means
3. The color printing apparatus according to claim 2, wherein when it is determined that no designation has been made, black image data is separated by said image data separating means and printing is performed in four colors.